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    <meta charset="utf-8">
    <title>菜鸟教程(runoob.com)</title>
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    <p>JavaScrip 内置构造函数。</p>
    <p id="demo"></p>
    <script>
        var myFunction = new Function("a", "b", "return a * b");
        document.getElementById("demo").innerHTML = myFunction(4, 3);
    </script>

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